The Counterfeit Coin Detector Patent Archive

Every device ever patented to catch a bad coin

Patented February 20, 1934

If an object in your hands says PAT. FEBRUARY 20, 1934, it may be one of these.

PatentTitleInventorOf
US 1,947,538SPURIOUS COIN DETECTORCecil H. UnderwoodOakland, California

All dates